by David Derbyshire
January 21, 2010
Fresh fears were raised over GM crops yesterday after a study showed
they can cause liver and kidney damage.
According to the research, animals fed on three strains of
genetically modified maize created by the U.S. biotech firm Monsanto
suffered signs of organ damage after just three months.
The findings only came to light after
Monsanto was forced to publish its
raw data on safety tests by anti-GM campaigners. They add to the
evidence that GM crops may damage health as well as be harmful to
The figures released by Monsanto were examined by French researcher
Dr Gilles-Eric Seralini, from the University of Caen.
Yesterday he called for more studies to check for long-term organ
'What we've shown is clearly not
proof of toxicity, but signs of toxicity,' he told New Scientist
magazine. 'I'm sure there's no acute toxicity but who's to say
there are no chronic effects?'
The experiments were carried out by
Monsanto researchers on three strains of GM maize.
Two of the varieties contained genes for
the Bt protein which protects the plant against the corn borer pest,
while a third was genetically modified to be resistant to the
glyphosate. All three strains are widely grown in America, while
one is the only GM crop grown in Europe, mostly in Spain.
Monsanto only released the raw data after a legal challenge from
Greenpeace, the Swedish Board of Agriculture and French anti- GM
Dr Seralini concluded that rats which ate the GM maize had
'statistically significant' signs of liver and kidney damage. Each
strain was linked to unusual concentrations of hormones in the blood
and urine of rats fed the maize for three months, compared to rats
given a non-GM diet.
The higher hormone levels suggest that animals' livers and kidneys
are not working properly.
Female rats fed one of the strains also had higher blood sugar
levels and raised levels of fatty substances caused triglycerides,
Dr Seralini reported in the International Journal of Microbiology.
The analysis concluded:
'These substances have never before
been an integral part of the human or animal diet and therefore
their health consequences for those who consume them, especially
over long time periods are currently unknown.'
Monsanto claimed the analysis of its
'based on faulty analytical methods
and reasoning, and does not call into question the safety
findings for these products'.